ISO Pascal reference manual

*ERROR 93 -- the name of the control variable is required here
The name of the variable to be used to control a FOR loop must be specified
immediately following the word FOR.
PROGRAM fail(output);
BEGIN
END.
FOR 1 TO 10 DO (no control variable}
writeln('hello');
*ERROR 94 -- this is not a variable and so may not be used to
control the FOR statement
A FOR statement must use a variable declared in the current block to
control the repeated execution of the controlled statement. This error
indicates that an attempt has been made to use something other than a
variable as the control variable.
PROGRAM fail(output);
TYPE cvar = 1..10;
BEGIN
END.
FOR cvar := 1 TO 10 DO {cvar is not a variable}
writeln('hello');
*ERROR 95 -- the control variable was not declared in
this block
The FOR loop control variable must be a local variable, that is, it must have
been declared in the VAR section of the current block. Note in particular
that a formal parameter to a procedure or function may not be used as a
control variable.
PROGRAM fail(output);
VAR global : integer;
PROCEDURE print; BEGIN
END;
FOR global := 1 to 10 DO (global not declared in 'print'}
writeln('printingg');
78 Pascal Issue 1